what is Partial views in razor .....

Layouts and sections are a powerful and effective technique for creating maintainable websites because they provide the ability to split a given web page into smaller, more focused parts. In addition to layouts and sections, Razor offers yet another compartmentalization technique called partial views, which are self-contained portions of markup that can be reused throughout the website. Partial views are also useful for
separating complex or lengthy portions of markup from a page, making them easier to read and understand (and by extension, easier to maintain).